The science behind the effects of extreme exertion on the human body and how the body adapts to the pressure engrossed 13 youngsters, ages 10 to 15, during a series of summer-camp lectures and experiments sponsored by Durango Discovery Museum last week.
They listened to a mountaineer’s adventures, went underwater with a diver, questioned a NASA engineer in Houston about the effects of zero gravity, tackled a climbing wall to learn how working the skeleton can save muscle energy and heard from an Ironman competitor on how to train and what to eat.
They traveled to space when they were patched through to the International Space Station to watch the daily activities of cosmonauts on a one-way camera. They later talked to a NASA engineer about the design of spacesuits that enable astronauts to leave their capsule to perform tasks, known as extra-vehicular activities.
Jen Lokey, the Discovery Museum’s curriculum and education programming manager, opened the weeklong program with an overview of the body systems and the effects of cold and altitude on the body.
The primary effect of ascent is the decrease in barometric pressure and the corresponding drop in available oxygen, Lokey said. Air is 21 percent oxygen, 78 percent nitrogen with traces of other gases at whatever elevation, but labored breathing occurs at high elevations because, with reduced air pressure there’s less air in a given space and, consequently, less oxygen.
The website of the Institute for Altitude Medicine in Telluride says that even at the town’s modest 8,750-foot elevation, people breathe the equivalent of 15 percent oxygen in air, compared with 21 percent at sea level. In Durango (6,512 feet), it’s just more than 16 percent.
Lokey explained that the body compensates for a shortage of oxygen by increasing the heart and respiratory rates and increasing the size of red blood cells to improve the delivery of oxygen.
Alec Johnson, who’s employed at Backcountry Experience and is a guide for Durango company Kling Mountain Guides, followed Lokey to recount his experiences on Mount Rainier (14,409 feet elevation) and Mount Shasta (14,179 feet).
Oxygen deprivation can affect decision-making and judgment, said Johnson, who is planning to soon tackle Argentina’s 22,387-foot-high Aconcagua.
“Decision-making under duress is important because an error can have serious ramifications,” he said.
The next day the students left the heights to learn firsthand the effects of water pressure from Terry Tucker at Splash Down Diving.
“There’s always something to see and learn underwater,” Tucker said. “We know more about the moon than we do about our oceans.”
After Tucker’s talk, the students assembled not on the seashore but at the Durango Community Recreation Center swimming pool, where Tucker outfitted them with scuba gear.
They learned that at sea level, the body is under 1 atmospheric pressure, or 14.7 pounds per square inch. But as soon as a body submerges, pressure increases immediately until at 33 feet below the surface the pressure has doubled.
The students performed maneuvers in about 5 feet of water.
Tucker taught them techniques to equalize the pressure in air pockets such as the ears, sinuses and diving mask.
The students on Friday afternoon hosted a public exhibition at the Discovery Museum’s adjoining education center to show what they had learned.
daler@durangoherald.com
